Step 1: DreamHost Control Panel

If your domain is not yet listed here, click the “Add Hosting to a Domain /
Sub-Domain” button near the top left of the page.

Scroll down to the “DNS Only” hosting section towards the bottom, and enter
your domain. Click the “Host DNS only!” button. Wait a few minutes for
processing.

Back on the Manage Domains page, click the “DNS” link directly under your
domain name.

In the “Add a custom DNS record to YOURDOMAIN:” section, enter the A record
for the domain or subdomain you wish to host, and the PTR record to be based
on. For example, if you want “mail.example.com” then “Name” will be “mail”,
“Type” will be “A” and “Value” will be your public IPv4 address for your
DreamCompute instance. Click “Add Record Now!”.

Repeat the last step as many times as needed to add additional A records for
domains you wish to host on your instance. If you add multiple records, our
system may not pick the one you wanted which requires the last step below. If
you only enter one, chances are it will pick the right one and get set on its
own after a few hours of DNS propagation time.

Step 2: Contact Support

Due to the possibly of multiple domains and multiple A records pointing to your
public IPv4 address, our system may not pick the one you want by default. To
remedy this, please contact our support team
and let us know the following:

Which domain or subdomain you want the PTR record to point to.

The public IPv4 address.

Our support team will make sure that your public IPv4 address has the right
record set and will push out a DNS update. After a wait of 4 or so hours for
DNS propagation, your PTR record should show up!

Step 3: Checking PTR Records

Please allow at least 4 hours for DNS propagation, and after this you can check
for the proper value. To do so from the command line:

[user@localhost]$ dig -x PUBLICIPADDRESSHERE

There are other websites that can help with this too, if you google for
“PTR lookup”.